Steam-boiler fire-box.



APPLICATlON FILED IUNES. [915.

Patented Nov. 30, 1915.

2 SHEETS-SHEET 1 WITNESSES Patented Nov. 30, 1915.

2 SHEETS SHEET 2.

a 0 .&R v w L D. M. LIGHT.

STEAM BOILER FIRE BOX.

APPLICATION FILED JUNE 5. 2915.

DAVID M. LIGHT, OF SPRINGFIELD, MISSOURI.

STEAM-BOILER FIRE-BOX.

Specification of Letters Patent.

' Patented Nov. 30, 1915.

Application filed June 5, 1915. Serial No. 32,268.

. the following is a specification.

My invention particularly relates to fireboxes for steam boilers of the locomotive type, and its object is to provide a firebox of such character which shall be of simple and ineX- pensive Construction, and ready applicability in any of the present standard forms of locomotive boilers, and shall afiord the practical advantages, among others, over those of the ordinary construction, of enabling the area of water heating surface to be substantially increased'and insuring a more rapid and effective circulation of water over the same; wholly eliminating the large number of side water leg stay bolts ordinarily required;

and affording read access to all of its constltuent members or purposes of cleaning,

repair, or renewal.

The improvement claimed is hereinafter fully set forth.

In the accompanying drawings: Figure 1 is a vertical longitudinal central section through the firebox and-the rear portion of the waist of a locomotive boiler, illustrating an embodiment of my invention; Fig.2, a view, the left hand half of which is a rear elevation of the firebox, and the right hand half, a vertical transverse section, on the line a; a: of Fig. 1; and Fig. 8, a horizontal section, on the line 1 3 of Fig. 1.

In the practice of my invention, I provide a firebox which is preferably, as shown, of

substantially rectangular horizontal sec tion, and which, preliminarily and generally considered, comprises, as essentials, what may be termed a top header, which is designated herein, as an entirety, by the reference symbol, A; a front transverse water leg, designated, as an entirety, by B; a back transverse water leg, designated, as an en tirety, by C and a plurality of water tubes, D, connecting the front andback water legs Y on each side of the firebox. Thestructural details of-the above recited members of the firebox, and their relation, one to another and to the waist of the boiler, will now be described.

The constituents of the top header, A, are

the outside roof sheet or wrapper sheet, 1,

and the, crown sheet, 2, of the firebox, the

roof sheet being, in the instance exemplified, shown as of the ordinary segmental. form, and as connected to the crown sheet by radial stays, 3. The form of the roof sheet and the particular means of staying the crown sheet, are not, however, essentials of connection with a firebox having a top'of the Belpaire' fiat or Player curved design, and with crown bars or any other preferred form of crown sheet stays.

The sides of the roof sheet, 1, are inwardly curved to a substantially semi-circular section, and connected by seams of rivets to the crown sheet, 2, thereby forming downwardly depending lateral water chambers on the top header, A, and making its transverse section substantially in the form of a crescent, as clearly shown in Fig. 2. Said lateral'water chambers are also preferably, as shown in Fig. 1, made of gradually increasin depth from their rear to their front my invention, as itis equally applicable in en s, thereby maintaining their bottoms parallel with the subjacent water tubes, D, hereinafter described, and imparting the maximum amount of water heating surface to the header. The. lateral water chambers may if preferred, be formed by the'interposition of separate sheets, 1, bent to semicircular transverse section,'betweenthe roof sheet and the sides of the crown sheet. The

are entirely open, for communication with the waist of the boiler and with the back water leg, C, respectively, and the front end of the roof sheet is connected by rivets to the rear waist sheet, 11, of the boiler.

The back water leg, G, is composed of the back head sheet, 4, and the door sheet, 5, which sheets are connected, by a seam of rivetsextending around the fire door openor S formed flanges, 45, the outer faces of which are connected to the flat sides of the door sheet by the seams of rivets, S. Stif'fening plates, l may, if desired, be interposed front and back ends of the top header, A,

- nected at each side by,

between the back head sheet and door sheet along their lines of riveted connection, and similar plates may also befitted between the tube sheet and throat sheet.

The front water leg, B, is composed of the tube sheet, 9, and the throat sheet, 10, which sheets are connected by stay bolts, 7, in the ordinary manner, and by seams of rivets, 8, at the sides of the sheets. A forwardly extending flange, 10", is turned on the throat sheet, for connection, by rivets, to the adjoining waist sheet, 11, of the boiler, and the tube sheet, 9 is provided, at its top, with a rearwardly extending flange, 9, which is connected by rivets to the front end of the crown sheet, 2. The connection of the tube sheet and throat sheet is made in a similar manner to that of the back head sheet and door sheet, as before described, the sides of the tube sheet being without flanges and those of the throat sheet being turned into reversed curve or S formed flanges, 10, the outer faces of which are connected to the flat sides of the tube sheet by the seams of rivets, 8?. p

The front and back water legs areconand the side water spaces of'the firebox formed by, a plurality of water tubes, D, which are expanded at their ends into the door sheet and tube sheet, and which, for thepurpose of ,promoting the circulation of'water, are preferably, as shown, upwardly and rearwardly inclined. The water tubes, D, aredisposed ateach side of the firebox, in two vertical rows, below the downwardly depending lateral water chambers of the top header, A, the tubes being set at slight distances apart,

and relatively staggered in the adjoining rows, in order to present the maximum attainable amount of water heating surface to i the calorificaction of the gases of combustion which circulate aroundthem. Removable plugs, 4 are fitted in the back head sheet, 4, oppositethe ends of the water tubes, for the purpose of permitting tube cleaners to be inserted when desired, and these tubes may be provided with smaller plugs, 4, to admit of the introduction OfWater for Washing out the tubes. The sides of the firebox, between the front and. back water legs, are closed by walls, 12, of fire brick or other suitable refractory material, which are'supported on longitudinal bearers, 1'3, and the side walls, 12, are covered and protected by casings, 12 of light plate metal. Air inlets, 12, may be formed in the lower rows of bricks of the side walls, to promote the uniform combustion of the fuel on the grate.

The bottoms of the front and back Water legs are closed by mud rings, 14, which are interposed between and riveted to the sheets of the water legs in the usual manner. Downwardly projecting lugs, 1%, formed on the mud rings, serve to'support the ends of the bearers,

.water leg composed of and a connected door sheet; and a plurality 18, of the side walls, and the grate bars and ash pan, which-latter members may be of any suitable and preferred form, and, as they are familiar to those skilled in the art, and do not form part of my present invention, they are not herein shown or described.

I claim as my invention and desire to se cure by Letters Patent:

1. The combination, in a steam boiler firebox, of a top header of substantially crescent shaped transverse section, composed of a roof sheet and a connected crown sheet, and having a downwardly depending water chamber on each of its sides; a front transverse water leg composed of a tube sheet and a connected throat sheet; a back transverse water leg composed of a back head a tube sheet and a connected throat sheet;

a back transverse a back head sheet of water tubes located below, and substantially parallel with, each of the lateral Water chambers of the top header, and connecting the front and back transversewater legs.

3. The combination, in a steam boiler firebox, of a top header composed of a roof sheet and a connected crown sheet; a front transverse water leg composed of a tube .sheet and a connected sheet having flat sides extending the full width of the throat sheet and being connected through a top flange to the front of the crown sheet, and the throat sheet having lateral flanges connected to the flat sides of the tube sheet; a back transverse water leg composed of a back head sheet and a connected door sheet, the back head sheet being connected through a top flange to the roof sheet and having lateralflanges, and

the door sheet having fiat sides extending a front transverse 1 throat sheet, the tube transverse water leg composed of a tube sheet and a connected throat sheet; a back transverse water leg composed of a back head sheet and a connected door sheet; a 5 plurality of Water tubes connecting the front and back transverse Water legs, on each side of the firebox; mud rings closing the bottoms of the water legs and having down- Wardly projectin lugs; Walls of refractory material closing the sides of the firebox; and 10 longitudinal bearers supporting said Walls and connected to the lugs of the mud rings.

DAVID M. LIGHT. Witnesses:

PETER SGHREINER. HORACE P. Dawns. 

